RADARSAT-1 Satellite

The following is a brief description of the RADARSAT-1 satellite, managed by the Canadian Space Agency (CSA), with data processing and distribution performed by MDA's Geospatial Services (formerly RADARSAT International), also of Canada, or by ACRES.

The RADARSAT-1 satellite was launched on 4 November 1995 and has a Synthetic Aperture Radar (SAR) sensor on board. This sensor can operate in a variety of imaging modes to suit a range of applications. Additional information on the RADARSAT-1 satellite and data applications can be obtained from the MDA's Geospatial Services (formerly RADARSAT International).

Sensor Parameters

The SAR sensor is an active microwave sensor capable of imaging the Earth regardless of time of day, cloud, haze or smoke over an area. The instrument is classified as "active" as it emits the microwave energy necessary to image the Earth's surface. In contrast, "passive" or "optical" sensors rely on the sun's reflected energy to image the Earth. More general information on SAR is available through NASA's Jet Propulsion Laboratory: What is Imaging Radar?

The SAR sensor on RADARSAT-1 has the unique capability to acquire data in any one of a possible 25 imaging modes. Each mode varies with respect to swath width, resolution, incidence angle and number of looks. Because different applications require different imaging modes, RADARSAT-1 gives users tremendous flexibility in choosing the type of SAR data most suitable for their application. A summary of the imaging modes and their parameters is shown below. The following diagram shows most of the image modes available.

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RADARSAT-1 Imaging Modes

Beam Mode	Beam Position	Incidence Angle (°)	Nominal Resolution (metres)	Nominal no. of Looks	Nominal Area (km)
Fine	F1 # F2 # F3 # F4 # F5 #	37 - 40 39 - 42 41 - 44 43 - 46 45 - 48	10	1 × 1	50 × 50
Standard	S1 S2 S3 S4 S5 S6 S7	20 - 27 24 - 31 30 - 37 34 - 40 36 - 42 41 - 46 45 - 49	30	1 × 4	100 × 100
Wide	W1 W2 W3	20 - 31 31 - 39 39 - 45	30	1 × 4	165 × 165 150 × 150 130 × 130
ScanSAR Narrow	SN1 SN2	20 - 40 31 - 46	50	2 × 2	300 × 300
ScanSAR Wide	SW1	20 - 50	100	2 × 4	500 × 500
Extended High	H1* H2* H3 H4 H5* H6	49 - 52 50 - 53 52 - 55 54 - 57 56 - 58 57 - 59	25	1 × 4	75 × 75
Extended Low	L1	10 - 23	35	1 × 4	170 × 170
* This option is currently unavailable from the RADARSAT-1 satellite.
# Ten additional Fine Beam Mode positions are now available by moving each position closer or further from nadir.

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RADARSAT-1 SAR Characteristics

Frequency	5.3 GHz
RF Band Width	11.6, 17.3 or 30.0 MHz
Band Name	C Band
Wavelength	56 mm
Incidence Angle	10 - 59 degrees
Ground Resolution	10 - 100 metres
Swath Width	50 - 500 km
Polarisation	HH*
* H=horizontal.

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Generalised Applications

General Application	Advantage
Tropical / coastal studies	Radar penetrates cloud, fog and rain
Coastal / lakes studies	HH polarisation best for land/water discrimination
Discerning man-made features	These features strongly reflect radar energy
Assessment of soil and vegetation moisture content	Amount of SAR backscatter is related to this
Disaster studies (Volcanic eruptions, dust storms or flooding)	Radar penetrates dust and cloud
Remote area studies	Global coverage
Geology	Structural studies; exploration
Land use (including agriculture and forestry)	Mapping and change assessment

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Enquiries and orders for Radarsat data

Customers should contact ACRES for satellite programming and for help in choosing the best product for their application. Customers may also seek help from other Australian organisations who may provide RADARSAT consultancy services and who are also distributors of other ACRES products.

The RADARSAT-1 satellite can be programmed in advance to acquire information over a particular area of interest. This means that a client's data requirements can be guaranteed, with no problems of cloud, haze or smoke.

Copyright

Special copyright conditions apply to the sale of RADARSAT-1 satellite data. To acknowledge these copyright conditions, customers are required to sign an ACRES End-User Licence prior to the purchase of any data.